|Vroh Bi, Irie|
Submitted to: Maize Genetics Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 1/5/2005
Publication Date: 3/10/2005
Citation: Yamasaki, M., Tenaillon, M., Vroh Bi, I., Schroeder, S., Sanchez-Villeda, H., Doebley, J., Gaut, B., Mcmullen, M.D. 2005. Genomic screening for domestication and improvement genes in maize [abstract]. Maize Genetics Conference. Paper No. 161. p. 118. Interpretive Summary:
Technical Abstract: Maize (Zea mays ssp. mays) was domesticated from teosinte (Zea mays ssp. parviglumis) through a single domestication event in southern Mexico between 6,000 and 9,000 years ago. This domestication event resulted in the original maize landrace varieties that were spread throughout the Americas by Native Americans, leading to adaptation to a wide range of environmental conditions. Starting with landraces, 20th century plant breeders selected inbred lines of maize for use in hybrid maize production. Both domestication and crop improvement involved selection of specific alleles at genes controlling key morphological and agronomic traits, resulting in reduced genetic diversity relative to unselected genes. The loss of genetic diversity in maize varieties involves not only directional selection, but also population bottlenecks and hitchhiking effects. Here we sequenced 1,095 maize genes from a sample of 14 inbred lines and chose 35 genes with zero sequence diversity as potential targets of selection. These 35 genes were then sequenced in a sample of diverse maize landraces and teosintes. Hudson-Kreitman-Aguadé tests and coalescent simulations of domestication were performed to test for selection. Four domestication and four improvement genes were identified as significant for selection by both analyses. Genomic screens for evidence of selection identified genes of potential agronomic importance even when gene function and the phenotype of interest are unknown.